Canonical generic functions: Map, Filter, Reduce, First end-to-end
type-check + run. Plus 20+ typer-only shape tests covering Apply,
Compose, ToMap, Swap, Box, Triple, ToSlice, Take, Send, Fill, Eq,
Values, Pair, Inspect, etc. Index synth (slice/array/map →
element type) added to typer.
v0 limitations stamped in tests: SX `/` is float (no int mod
emulation), `var r []T` indistinguishable from unbound, single-name
constraints opaque (no type-set arithmetic).
Shape locked in: "the parser recognizes shapes, the validator
recognizes roles." Same AST + different role-validators = different
guest semantics. Diary documents this as the lemma the kit should
extract — three deliverables (binding-groups, control-flow sentinels,
index synthesis) now all instantiate it.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
gp-parse-type-params consumes the optional [NAMES CONSTRAINT, ...]
clause after a func name. AST stays backward-compatible: 5-slot
func-decl when no [...] is present, 6-slot when it is.
Typer binds each type-param name as (:ty-param NAME CONSTRAINT) so
body's (:ty-name "T") references resolve. Eval is type-erasing —
ignores type info, dispatches by name + arity.
10 new tests: parse (3), types (5), eval (2). Total 527/527.
Shape: the field binding-group from the canonical kit now feeds
6 consumers (struct fields, var-decls, const-decls, params,
receivers, type-params). Confirms it as a TRUE cross-deliverable
shape — sister-plan diary documents the 5 roles binding-groups
take and why the kit should expose ONE parser + pluggable validators.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Phase 3 cont. The headline Go-distinguishing typing feature: interfaces
are satisfied *structurally and silently* — no `implements` declaration,
no nominal subtyping. Any type whose method set contains all the
interface's methods (with matching signatures) satisfies it.
Method declarations now type-check via go-check-method-decl:
* Receiver type extracted (T or *T → "T") via go-extract-recv-ty-name.
* Method signature (:ty-func PARAMS RESULTS) bound under a mangled
key "#method/RECV-NAME/METHOD-NAME" in ctx.
* Body checked with receiver + params extended into the body ctx.
go-iface-satisfies? CTX TY-NAME IFACE-TYPE walks the interface's
:method elements; for each, looks up #method/TY-NAME/METHOD-NAME and
compares (PARAMS, RESULTS) tuples. Embedded interfaces (:embed
elements) skipped in v0 — recursive interface resolution later.
Tests:
* method-decl binds under #method/Point/String
* pointer-receiver method also keys the base type
* Point with String() satisfies interface { String() string }
* empty type does NOT satisfy Stringer
* arity-mismatch method fails satisfaction
* multi-method satisfaction works
* partial method-set fails
types 72/72, total 377/377. Phase 3 sub-deliverable list is now
substantially complete; only AST-path error context remains as a UX
sharpener.
Sister-plan static-types-bidirectional diary updated with the
**constraint-satisfies? pluggable predicate** kit-API proposal —
third pluggable point after synth/check + assignable?. Go interfaces,
Haskell typeclasses, Rust traits, and TS structural subtyping all
answer "does this value-type fit this constraint-type?" with
different machinery; the kit's check uses constraint-satisfies? when
EXPECTED is itself a constraint type.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Phase 3 cont. Adds:
* go-classify-literal-string — heuristic detection of literal kind
from the value-string (parser strips lexer's kind tag; flagged for
follow-up to extend AST shape).
* go-synth-literal — :ty-untyped-int / -float / -imag / -string.
* go-synth-binop — arithmetic, bitwise, comparison, logical ops with
untyped-constant unification:
untyped-int + untyped-float → untyped-float
untyped + typed → typed
comparison ops → bool
logical ops → bool
* go-untyped? + go-type-assignable? — pluggable assignability that
swaps in where structural equality used to gate go-check. Untyped
int assignable to any numeric type; untyped float assignable to
float/complex; untyped string to string.
**Canonical Go pitfall handled correctly**: `var x float64 = 42 / 7`
parses to a binop, synth produces :ty-untyped-int (since BOTH operands
are untyped, the int division stays in the int domain), and check
against float64 returns :ok via assignability. Wrong implementations
that float-coerce eagerly would give 6.0; the right behaviour is
"compute 6 as int, then convert to float64 = 6.0".
Verified by test "binop: 42 / 7 assignable to float64 (canonical
pitfall)" and the type-only test "binop: 42 / 7 — untyped int".
Sister-plan static-types-bidirectional diary updated with the
**pluggable-assignable-predicate** kit-API proposal:
(check-with assignable? CTX EXPR EXPECTED)
Each consumer plugs in its own variance discipline (Go untyped-flow,
TS structural subtyping, Rust lifetime-aware identity) without
rewriting synth or the judgment skeleton.
types 28/28, total 333/333.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
First slice of Phase 3 (bidirectional type checker).
lib/go/types.sx defines:
* go-ctx-empty / go-ctx-extend / go-ctx-lookup — context as a value.
* go-ctx-extend-field — consumes the (:field NAMES TYPE) shape from
the parser, binding every name to the shared type. This is the
cross-deliverable validation of the :field binding-group
observation made during Phase 2 func decls: parser produces it,
type checker consumes it, same shape end-to-end.
* go-predeclared — true / false / nil baked in. Full list expanded
on demand.
* go-synth — currently handles variable lookup; literals / calls /
binops follow in subsequent iterations.
* go-check — v0 defers to synth + structural type equality. Untyped-
constant flow and assignment-compatibility relations land later.
* Type errors carry first-class tags (:unbound, :mismatch,
:unsupported-synth) so consumers and tooling can dispatch.
Conformance.sh wired with new types suite. Scoreboard cleanup: drop
the "pending" types row since the suite is now real.
types 12/12, total 317/317. Phase 3 underway.
Sister-plan static-types-bidirectional diary updated with the
synth/check shape: judgment skeleton, error tag structure, and the
proposal that `check` should accept a `subtype?` predicate parameter
so each consumer (Go untyped-constants, TS variance, Rust lifetimes)
plugs in its own variance discipline without rewriting the judgment.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Adds Go func and method declarations:
func main() {}
func add(x, y int) int { return x + y }
func mix(x int, y string) {}
func divmod(a, b int) (int, int) {}
func sig(x int) int (no body)
func (p *Point) String() string { ... } (method, pointer recv)
func (s Stack) Len() int { ... } (method, value recv)
func nested() { if true { x := 1; { y := 2 } } } (nested braces)
New gp-parse-decl-param-group implements named-greedy disambiguation:
collects consecutive 'ident [, ident]*' then parses a type. Anonymous
mixed lists like 'func(int, string)' are a known limitation (parser
treats first ident as a name); flagged in plan.
gp-skip-block! brace-balances over the body; the AST stores ':body'
as a sentinel until statement parsing lands. Methods use the receiver
parameter shape directly.
AST:
(list :func-decl NAME PARAMS RESULTS BODY)
(list :method-decl RECV NAME PARAMS RESULTS BODY)
**All five `:field` binding-group consumers now exist** across the
parser: struct fields, var, const, func params, method receivers.
That's strong cross-deliverable validation of the ast-binding-group
proposal from Blockers — five different declaration contexts, one
shared shape.
This is the chisel-relevant insight for sister plan static-types-
bidirectional: an entry has been appended to its design diary
describing how `:field` will be the load-bearing input shape for
the bidirectional checker's `check Γ e T` judgment across these
contexts.
parse 132/132, total 261/261.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
- go-on-sx.md: rewrite of 2026-04-26 draft to integrate lib/guest framework.
Adds Phase 3 (independent bidirectional type checker — first static-typed
guest), Phase 10 (extraction enabler), chisel discipline, conformance
scoreboard model. Phases 1-2 now consume lib/guest/core lex+pratt+ast.
- lib-guest-scheduler.md: NEW. Extraction plan for the fork/yield/block/
resume scheduler shared by Erlang (addressed processes + mailboxes) and
Go (anonymous channels + goroutines). Two-language rule blocks extraction
until both consumers independently work; rejected-extraction is a valid
outcome.
- lib-guest-static-types-bidirectional.md: NEW. Sister to lib/guest/hm.sx.
Bidirectional checker kit (synth/check judgments, pluggable subtype +
unify) for the languages HM doesn't fit — Go, Rust, TS, Swift, Kotlin,
Scala 3, Hack. First consumer: Go-on-SX. Second TBD; recommendation
TypeScript.
The three plans cross-reference each other. Go-on-SX implements scheduler +
checker independently of the kits; extraction is its own workstream once
two consumers exist.
